Limitations of Traditional Capacity Equations for Long Curb Inlets

2017 ◽  
Vol 2638 (1) ◽  
pp. 97-103 ◽  
Author(s):  
Frank E. Schalla ◽  
Muhammad Ashraf ◽  
Michael E. Barrett ◽  
Ben R. Hodges
Keyword(s):  
Laboratory Experiment ◽  
Recent Work ◽  
Water Surface ◽  
Surface Profile ◽  
Full Scale ◽  
Substantial Portion ◽  
Design Storm ◽  
Potential Safety ◽  
Standard Design ◽  
Inlet Length

Recent work with full-scale experiments indicates that there are fundamental problems with standard curb inlet design equations when applied to depressed curb inlets of 10 ft (3 m) or longer. A full-scale laboratory experiment showed that the latter part of a long inlet does not have a simple linear water surface profile at 100% interception, which is assumed for the form of Izzard’s equation that is adopted for many common design approaches [including the Hydraulic Engineering Circular 22 (HEC-22) design equations recommended by FHWA]. For a long inlet, thin flow sheets were observed for a substantial portion of the inlet length, which is consistent with previous observations that have not been incorporated into standard design equations. Experimental results indicate that the HEC-22 design equations significantly overestimate the interception capacity of long, depressed curb inlets for an on-grade gutter. This issue has potential safety implications in that the gutter bypass and spread for a design storm will be larger than expected for such inlets. The present work is preliminary, so an L2 measure previously proposed by Izzard is recommended as a maximum inlet length pending the outcome of further studies.

Effect of mesh on CFD aerodynamic performances of a container ship

2020 ◽  
Vol 20 (3) ◽  
pp. 343-353
Author(s):  
Ngo Van He ◽  
Le Thi Thai
Keyword(s):  
Water Surface ◽  
Reference Model ◽  
Full Scale ◽  
Scale Model ◽  
Container Ship ◽  
Ansys Fluent ◽  
Remarkable Effect ◽  
Aerodynamic Performances ◽  
Mesh Convergence

In this paper, a commercial CFD code, ANSYS-Fluent has been used to investigate the effect of mesh number generated in the computed domain on the CFD aerodynamic performances of a container ship. A full-scale model of the 1200TEU container ship has been chosen as a reference model in the computation. Five different mesh numbers for the same dimension domain have been used and the CFD aerodynamic performances of the above water surface hull of the ship have been shown. The obtained CFD results show a remarkable effect of mesh number on aerodynamic performances of the ship and the mesh convergence has been found. The study is an evidence to prove that the mesh number has affected the CFD results in general and the accuracy of the CFD aerodynamic performances in particular.

scholarly journals FEM analysis of water surface profile using VOF Method

2021 ◽  
Vol 1116 (1) ◽  
pp. 012112
Author(s):  
Avdhesh Kumar Sharma ◽  
Prashant Kumar Dixit ◽  
Shashank Srivastava
Keyword(s):  
Water Surface ◽  
Surface Profile ◽  
Fem Analysis ◽  
Vof Method ◽  
Water Surface Profile

scholarly journals A reduced-complexity model for river delta formation – Part 1: Modeling deltas with channel dynamics

2015 ◽  
Vol 3 (1) ◽  
pp. 67-86 ◽  
Author(s):  
M. Liang ◽  
V. R. Voller ◽  
C. Paola
Keyword(s):  
Sediment Transport ◽  
Flow Field ◽  
Water Surface ◽  
Surface Profile ◽  
River Delta ◽  
Suspended Sediment Transport ◽  
Channel Dynamics ◽  
Wide Range ◽  
Delta Formation ◽  
Reduced Complexity

Abstract. In this work we develop a reduced-complexity model (RCM) for river delta formation (referred to as DeltaRCM in the following). It is a rule-based cellular morphodynamic model, in contrast to reductionist models based on detailed computational fluid dynamics. The basic framework of this model (DeltaRCM) consists of stochastic parcel-based cellular routing schemes for water and sediment and a set of phenomenological rules for sediment deposition and erosion. The outputs of the model include a depth-averaged flow field, water surface elevation and bed topography that evolve in time. Results show that DeltaRCM is able (1) to resolve a wide range of channel dynamics – including elongation, bifurcation, avulsion and migration – and (2) to produce a variety of deltas such as alluvial fan deltas and deltas with multiple orders of bifurcations. We also demonstrate a simple stratigraphy recording component which tracks the distribution of coarse and fine materials and the age of the deposits. Essential processes that must be included in reduced-complexity delta models include a depth-averaged flow field that guides sediment transport a nontrivial water surface profile that accounts for backwater effects at least in the main channels, both bedload and suspended sediment transport, and topographic steering of sediment transport.

scholarly journals PENGARUH BENDUNG TERHADAP PROFIL MUKA AIR SUNGAI BATANG GADIS

2014 ◽  
Vol 8 (1) ◽  
pp. 1
Author(s):  
Sudarmanto ,
Keyword(s):  
Numerical Integration ◽  
Cross Section ◽  
Water Surface ◽  
Surface Profile ◽  
Uniform Flow ◽  
Flood Discharge ◽  
Before And After ◽  
Numerical Integration Methods ◽  
The Village ◽  
River Cross Section

Placement of the weir in the river Batang Gadis will cause population anxiety in the village Pulungan which located upstream weir as far as 3 km, due to a weir can cause water surface profile of the river getting higher and ultimately to increase the pool of flooding in residential areas.Assuming modeling of river a uniform flow, river cross-section has a rectangular shape with width 50 m and 40 m, the roughness Manning 0.0025, the profile of water flow floods that occurred in 2 yaears, 25 years, and 100 years before and after the existing weir can be calculated by numerical integration methods.  From the calculation, the length of the water behind the weir is 1.4 km upstream towards the weir, which means that the depth of the water level rises to as far as 1.4 km and after that the depth of water before and after there the weir is same. Because the village Pulungan located 3 km to the upstream, the weir did not affect the increase in the flood waters in the village Pulungan. At 2 years flood discharge does not cause inundation in the village Pulungan, but the flood discharge 25 years and 100 years has led to inundation in the village Pulungan with the depth of each pool 0.971 m and 1.675 m. Keywords: uniform flow, numerical integration, inundation, flood discharge.

scholarly journals Development of GIS-based Python scripts to calculate a water surface profile on a landscape for wetlands decision-making

2020 ◽  
Vol 22 (3) ◽  
pp. 628-640
Author(s):  
Zhentao Wang ◽  
Kathleen M. Trauth
Keyword(s):  
Water Surface ◽  
Research Effort ◽  
Land Use Changes ◽  
Surface Profile ◽  
Euler’S Method ◽  
Landscape Characteristics ◽  
Landscape Processes ◽  
Mitigation Wetland ◽  
Elevation Model ◽  
Channel Hydraulics

Abstract Wetlands provide many benefits for humans and the natural environment, but land-use changes have reduced their number and areal extent. Interest has grown in examining the landscape to determine those locations where, with minimal effort, it might be possible to develop a mitigation wetland – a location with sufficient water over a sufficient period of time to develop and maintain wetland functioning. This paper proposes a methodology to support the examination of the landscape for mitigation purposes through the application of open channel hydraulics principles to flow over a landscape. The methodology is part of a larger research effort ultimately combining hydrology and hydraulics, along with the landscape processes of infiltration and evapotranspiration, to perform a water balance assessment. Specifically, the methodology is implemented through readily available geographic information system tools along with Python scripts written for this study. The Python scripts automatically extract landscape characteristics from a digital elevation model and calculate hydraulic parameters that are used to determine water surface profiles using the Modified Euler's method. Multiple tests show that the script accurately produces profiles of flow between depressions over a landscape. Such determinations are the first step in understanding where water might exist on the surface to support mitigation wetland functions.

Sign in / Sign up

Export Citation Format

Share Document